1. Field of the Invention
The present invention relates to a new composition which can be used in the pharmaceutical, dietetic and cosmetic fields, and more particularly a new composition combining plant extracts of defined titers and essential oils providing enhanced effects.
2. Description of the Related Art
For many years, various natural substances have been used because of their pharmacological and cosmetological properties. Plants are sometimes used directly, simply dried and packaged in bulk after harvest, cut to different degrees, or alternatively ground, in order to make infusions, or sprayed at room or cold temperature. In all cases, the preservation of dry plants, in bulk or treated as indicated above, can only be achieved for a relatively short period of time because preservation for a period of a few months, or even a few weeks, causes loss of their properties which are often linked to components which are very volatile or sensitive to oxidation.
Fine pulverization of a plant increases the surface area of contact between the content of the plant cells and the ambient air and promotes their impairment, to the extent that it is often necessary to preserve the powders under vacuum or under an inert gas atmosphere in order to preserve their properties. Furthermore, for example in the case of grinding for the preparation of powders, it is often necessary to use grinders cooled with liquid nitrogen in order to avoid heating which may cause the loss of the volatile substances.
Among the various known forms of presentation, dry extracts, as well as essential oils, also called plant essences are often used.
Dry extracts are generally obtained by extracting the dry plant with water, alone or mixed with ethanol in variable quantities. The extracted juices are concentrated and then dried and mixed with excipients intended to facilitate the drying and the preservation. Depending on the techniques used, it is possible to obtain between about 0.15 g and 1 g of dry extract for 2 g of dry plant.
The dry extracts prepared by conventional techniques are generally hygroscopic and their preservation is difficult.
The plant extracts may also be incorporated, as adjuvants, into compositions, as described for example in patent FR-A-2,688,137 relating to moisturizing cosmetic compositions.
Aromatic plants contain on average 2% by weight of an odorous substance, also called "essence", which is a natural secretion of the plant organism. Once extracted from the plant, generally by steam distillation, it is called "essential oil".
As a result of their chemical composition, most essential oils have antiseptic and bactericidal properties. Depending on the botanical species, they may have specific properties which have been the subject of a very large number of studies for years, and which have allowed their use for external use and for internal use, in the cosmetic and therapeutic fields. Essential oils are more particularly used in aromatherapy for the treatment of various infectious states, either as principal therapeutic agent, or as adjuvant. For example, patent FR-A-2,670,386 describes a cosmetic composition containing an essential oil from basil intended to serve as repellent against certain insects.
However, on the one hand, the commercially available plant extracts generally exhibit insufficient stability, which further decreases their efficacy, and, on the other hand, it is known that essential oils are extremely sensitive to oxidation, and their preservation should therefore be carried out in the absence of air. Furthermore, essential oils should be used with care, and it is considered that it is necessary to avoid administering them separately, but that on the contrary they should be mixed with various excipients because of the unpleasant sensations which they cause in contact with the mucous membranes in the mouth.
The result is that the efficacy of treatments is greatly limited, and, even in the case of gelatin capsules, knowing that it is often necessary to administer more than 10 g of plant per day in order to obtain a favorable result, the user would have to take more than 50 gelatin capsules per day in order to be able to hope to obtain an effective treatment.
The same applies to the other conventional forms, such as infusions, decoctions or tinctures. Thus, by using conventional techniques, useful results can only be hoped to be obtained by taking each day quantities at least equal to 6 infusions or 60 g of tincture at 1/5 or of homeopathic stock tincture at 1/10 of fresh plant, containing alcohol at a high titer, of the order of 60 volumes. It is of course impossible to envisage taking such quantities. Likewise, the essential oils formulated by conventional techniques can only be used diluted in alcoholic solutions with high titers.
Patent FR-A-2,572,935 describes a composition for dietary use comprising a substrate consisting of a plant powder, containing an essential oil obtained from the same plant. The essential oil should be heated so as to be incorporated into the substrate, and the result is a volatilization of most of the oil, and a degree of instablilty of the composition.
A need therefore exists for effective and stable compositions which can be used in small quantities and which allow simple administration of the essential active ingredients of plants.